The invention relates to a pulse radio technique and, more concretely, to radar system designs and the one can be used in radar system of aviation, sea and river transport, other transport means, as well as for mapping earth surface, meteorological, ecological and other researchs of atmosphere, and other aims. It is the most perspective to use this invention in ground apparatus of small and middle sized aerodromes and navigation apparatus of aircrafts. These navigation apparatus can be designed for operating at fires, mountains, fog or low clouds.
It is known pulse radar systems created on the basis of frequency-agile magnetrons and using a tracking of a resonant frequency of magnetron oscillating system ("cold frequency" of magnetron) during a pause between pulses. For example, the radar system constructed on the basis of the magnetron YJ 1172 Philips Corporation (prospects "Pulsed Magnetron X-band YJ 1172" or "Frequency Agility Packages") comprises said frequency-agile magnetron receiving a signal from a low power source (a local oscillator) tuned by a varactor scheme. During a pause between pulses, a tracking of magnetron frequency is fulfilled by laying a signal, frequency 4 MHz, on the tuning voltage of said low power source and measuring a phase of resulted signal coming from a tracking detector after its reflection by the magnetron.
A coarse tuning of a frequency of the local oscillator has been begun by a synchronizing pulse about 1 .mu.s before the magnetron generates its pulse. A precise tuning of a frequency of that oscillator is being fulfilled in the process of generating the magnetron pulse.
That construction of the radar system permits to set a local oscillator at the frequency providing an intermediate frequency of a receiver rather precise, if the intermediate frequency of the receiver is nearby to the difference between "cold frequency" of the magnetron in the pause between pulses and the frequency of the signal, generated by the magnetron.
However, that construction does not provide operation of the radar system for predetermined frequencies of any pulse, especially for high destabilizing factors and changes of tuning frequency rate in the operation process. This conducts to a limitation of information from the radar system, a decrease of its frequency agility and a reduction of the reliability of the radar system.
Besides that, a necessity of fast tuning of frequency during a pause between pulses does not permit to use the most stable, fixed local oscillators. The system of tuning of frequency with an use of the additional source of the signal, frequency 4 MHz, and the measuring of a phase of the resulted signal after a tracking detector make the construction of the radar system much more complicated and its operation less reliable because of additional possible defects in the system of tracking and tuning.
An essential defect of that construction is also impossible to realize operation at one or a few frequencies fixed with high accuracy, if a vibration and other destabilizing factors influence changing a magnetron frequency.
This decreases the universality and the reliability of that radar system in addition.